Select whole script what is writed in that file what I give ya. then CTRL+C (copy)
Open UDK
select viewport to be active (just move camera). and type CTRL+V. Then search for 'green, blue and red arrow (moving arrows), there will be your waterfall, just move them to place you want, but remember, there's a water problem, so only one way to select water is to do it in 'no 3D' viewport. If map is small, you can always select water by (generic browser-> scene). But you don't need it if you place it correctly...
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